GeForce GTS 250 1GB vs Radeon HD 3870 X2 1GB

Intro

Compare those specs to the Radeon HD 3870 X2 1GB, which comes with core clock speeds of 825 MHz on the GPU, and 1126 MHz on the 1024 MB of GDDR4 memory. It features 320(64x5) SPUs along with 16 TAUs and 16 Rasterization Operator Units.

(No game benchmarks for this combination yet.)

Power Usage and Theoretical Benchmarks

Memory Bandwidth

The Radeon HD 3870 X2 1GB should in theory perform much faster than the GeForce GTS 250 1GB overall. (explain)

Radeon HD 3870 X2 1GB		144128 MB/sec
GeForce GTS 250 1GB		70400 MB/sec
	Difference: 73728 (105%)

Texel Rate

The GeForce GTS 250 1GB will be quite a bit (about 79%) better at anisotropic filtering than the Radeon HD 3870 X2 1GB. (explain)

GeForce GTS 250 1GB		47232 Mtexels/sec
Radeon HD 3870 X2 1GB		26400 Mtexels/sec
	Difference: 20832 (79%)

Pixel Rate

The Radeon HD 3870 X2 1GB is quite a bit (more or less 124%) faster with regards to full screen anti-aliasing than the GeForce GTS 250 1GB, and also will be capable of handling higher screen resolutions without slowing down too much. (explain)

Radeon HD 3870 X2 1GB		26400 Mpixels/sec
GeForce GTS 250 1GB		11808 Mpixels/sec
	Difference: 14592 (124%)

Please note that the above 'benchmarks' are all just theoretical - the results were calculated based on the card's specifications, and real-world performance may (and probably will) vary at least a bit.

One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.

Price Comparison

Specifications

Memory Bandwidth: Memory bandwidth is the maximum amount of information (measured in megabytes per second) that can be moved past the external memory interface in a second. It's worked out by multiplying the interface width by the speed of its memory. If the card has DDR type memory, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the memory bandwidth, the better the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are applied in one second. This is worked out by multiplying the total number of texture units by the core speed of the chip. The better the texel rate, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip could possibly record to the local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate also depends on quite a few other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the max fill rate.